Use of flash storage devices has been rapidly increasing over the years because they are portable and they have small physical size and large storage capacity. Flash storage devices come in a variety of designs. Some storage devices are regarded as “removable”, which means that a user can move them from one host device (e.g., cellular phone) to another or use multiple storage devices with one host device by swapping storage devices engaged by such host device. Other storage devices are regarded as “embedded”, meaning that they are built into and not intended to be removed by the user from the host device.
A host may need to operate with various kinds of removable storage devices, be it presently existing or future storage devices (e.g., SD cards, UFS cards, UHS-II cards, etc.). Various storage devices use or may be designed to use different kinds of protocols. To this end, the host device would have to accommodate different protocols, and this has typically required separate interfaces for the different cards and protocols. Also, the host may have to accommodate different storage device communication topologies.
Providing a host with large number of interfaces that support different protocols and topologies for communicating with various storage devices is not always practical and effective. Hence, there is a need to address this problem with a better approach.